MONDAY, April 21 (HealthDay News) — The most deadly melanoma skin cancers occur on the scalp and neck, says a University of North Carolina at Chapel Hill (UNC) study.

Researchers analyzed 51,704 melanoma cases in the United States and found that patients with scalp or neck melanomas died at 1.84 times the rate of patients with melanoma elsewhere on the body, including the face or ears.

The five-year survival rate for patients with scalp-neck melanomas was 83 percent, compared with 92 percent for patients with melanomas at other sites. The 10-year survival rate was 76 percent for scalp-neck melanomas and 89 percent for other melanomas.

The findings confirm that melanoma patient survival rates differ depending on where the cancer first appeared, the researchers said. The study was published in the April issue of the Archives of Dermatology.

Doctors need to pay close attention to the scalp when examining patients for signs of skin cancer, said senior author Dr. Nancy Thomas, an associate professor of dermatology in the UNC School of Medicine and a member of the UNC Lineberger Comprehensive Cancer Center.

"Only 6 percent of melanoma patients present with the disease on the scalp or neck, but those patients account for 10 percent of melanoma deaths. That's why we need to take extra time to look at the scalp during full-skin examinations," Thomas said in a prepared statement.

There has been debate about whether scalp and neck melanoma is more deadly primarily because it's diagnosed later than melanomas in other locations, but this study indicates that the presence of melanoma on the scalp or neck is, in itself, an indicator of poorer patient prognosis.

"We think there's something different about scalp and neck melanomas. This gives us directions for research to look at tumor cell types in those areas at the molecular level and to see if there are differences. I'm interested in identifying the mutations that drive malignancy," Thomas said.

The patients included in study were non-Hispanic white adults in nine states who were first diagnosed with invasive melanoma between 1992 and 2003. Patients with scalp-neck melanomas were more likely to be male and were an average age of 59 years, compared to 55 years for those with other melanomas.

Scalp-neck melanomas were thicker (0.8 millimeters) than other melanomas (0.6 millimeters) and more likely to be ulcerated. The study also found that lymph node involvement was more common in cases of scalp-neck melanomas.

—Robert Preidt

SOURCE: University of North Carolina at Chapel Hill, news release, April 21, 2008